Loom



M. PAABO Aug. 22, 1950 LOOM 3 Sheets-Sheet 1 Filed Aug. 12, 1946 Aug. 22, 1950 M. PAABo 2,519,786

LOOM

Filed Aug. 12, 1946 3 Sheets-Sheet 2 I IHIIII EQ Aug. 22, 19543 M. PAABO 2,519,786

LOOM

Filed Aug. 12, 1946 3 Sheets-Sheet 3 W aei l Patented Aug. 22, 1950 LOOM Max Piiiibo, Norrkoping, Sweden Application August 12, 1946, Serial No. 690,021 In Sweden August 11, 1945 7 Claims. (Cl. 139-127) (Granted under the provisions of see. 14, act of March 2, 1921; 357 0. G.

This invention relates to a loom of that type weft thread from a stationary spool, a nozzle for blowing the weft thread through the shed between the warp threads by means of a blast of compressed air, possibly mixed with a fine powder, and means for cutting the weft thread at the entrance end of the shed, a receiving funnel, opening in the direction of the shed, being arranged at the exit end of the shed, in which funnel a suitably reduced pressure is maintained. In previously known looms of this type the nozzle through which the weft thread is blown through the shed between the warp threads, is arranged on the lay of the loom. This is very disadvantageous as during the weaving faults easily result from this arrangement. Particularly when producing broad textile fabrics with these looms great difficulties arise, as for each weft a relatively long length of the weft thread must be unwound and this length is swinging forward and backward with the lay. Thereby the thread loop runs the risk of getting entangled in adjacent machine parts, particularly when a current of air passes the loom. Also the twisting of the thread may cause trouble in this connection. Another disadvantage with the known constructions is that flexible tubing leading from the source of compressed air to the nozzle must be arranged as the nozzle is swinging forward and backward with the lay. Such tubing is not durable and leakage easily results from their movements at their articulated points.

The disadvantages outlined above are fully overcome in the present invention by the fact that the nozzle and the means for unwinding the weft thread are stationary arranged on the loom. Consequently they do not take part in the reciprocating movement of the lay. Movable pipings to the nozzle are not necessary. The means for unwinding the weft thread may now be arranged in such a way, that the thread is-sufiiciently guided up to the moment when the length of thread is thrown through the shed by the air blast.

For a full understanding of the features and" principles of the invention reference is had to the accompanying drawings, in which Fig. 1 is a front view of a loom, showing the loom in the position it occupies the moment after the weft thread has been blown through the shed.

Fig. 2 is a similar view of the loom, showing its position at the moment when the reed is ap- 2 proaching the fell .to push the weft thread against the fell of the fabric.

Fig. 3 is a view on a larger scale showing the loom in vertical section on the line III--III, Fig. 1.

Fig. 4 is a similar section on the line IV--IV, Fig. 2.

Fig. 5 is a plan view of another embodiment of the unwinding means.

Fig. 6 is an end view of said means.

Fig. 7 is a vertical section on the line VII-VII, Fig. 6.

For the sake of clearness the stand of the loom has been left out in the drawings. The warp threads I, which are led substantially vertically through the loom, pass the reed 2 in the known manner which is held to the lay 4 of the loom by means of elastic clamps 3. The lay is pivoted on a shaft 5 carried bythe stand, so that the reed during the working of the loom describes an arc-shaped path in a vertical plane. At 1 and 8 are indicated two harness frames for creating the shed 9 between the warp threads I.

In the embodiment shown in Figs. 1-4 the weft thread It) is unwound from a stationary spool II and is led through a friction device braking the feeding of the weft thread, which device consists of two discs l2, I3, the latter of which is axially displaceable on a bolt l4, and is pressec against the other disc I2 by means of a coil spring l5. Further the weft thread It passes through a thread guide It and is wound one or more turns and/ or a fraction of a turn on to a rotating drum I! on which a catch I8 is arranged. In,the,,.ex.--.

ample illustrated the catch I8 consists of the outer end of a double armed lever l9 pivoted at 20, the opposite arm 2| of which cooperates with a cam disc 22 in such a way that the catch i8 at a definite moment of the rotation of th e drum I1 is drawn inside the periphery of the drum. The drum I1 and the cam disc ZZ are both constantly rotating but the cam 22 rotates at a slower rate of speed than the drum I! so that the catch l8 will operate in the manner described. The weft thread is then led through a passage 23 of a nozzle 24 which is directed with its mouth against the shed 9. A passage 25 issuing into the thread passage 23 is connected to a source of supply-of compressed air (not shown), and delivers compressed air through the necessary valves (not shown) to the nozzle, needed for blowing the weft thread through the shed 9. At the entrance end of the shed a pair of scissors 26 is arranged, the one somewhat shorter leg 21 of which is attached to a fixed part 28 of the stand, while the other leg 29 of the pair of scissors is provided with a roller or ball 30 for cooperation with a rotating cam plate 3| in such a way, that when the cam of the cam plate passes the roller or ball 30 on the leg 23, said leg is swung against the leg 21 (Fig. 3) for cutting the weft thread. When the reed upon the downward movement of the lay 4 pushes the weft thread introduced in the shed 9 against the fell of the fabric 33, the weft thread is forced in between the cutting edges of the legs 21, 23 (Fig. 4) by means of a thread guide 32 placed on the reed 2 at the entrance end of the shed 9, whereafter the cutting takes place. The leg 23 returns to its initial position under the action of a coil spring 34. At the exit end of the shed 8 a funnel 35 is arranged in alignment with the nozzle 24, which funnel is directed with its mouth against said nozzle and is connected to a source of vacuum (not shown). Said funnel is adapted to receive the free end of the weft thread when this end has passed through the shed. The reed 2 or the lay 4 carries also a guard 36 of any suitable construction which is only diagrammatically shown in the drawing and which forms no part of the claimed invention. Said guard is arranged in such a way that it is positioned in front of the receiving funnel 35 when the reed is in its initial position (Fig. 1). When the reed effects its downward movement in order to push a weft thread against the fell of the fabric, and the thread spool is empty or the weft thread does not reach the receiving funnel 35 for some reason or other, an impulse is given in any known manner, preferably by electric means, to the motor or coupling of the loom, whereby the loom is stopped.

The operation of the loom will be apparent with desirable clearness from the above description. After the necessary length of the weft thread H) has been wound onto the drum I! by the catch III, which length should somewhat exceed the width of the textile fabric part to be woven, said catch is drawn inside the periphery of the drum in the manner indicated above. The loose thread loop formed in this way is blown by the compressed air coming from the passage 25 which is momentarily connected by means of devices provided to that effect (not shown), through the shed 9, the thread, guided by the nozzle 24, passing thereby beneath the thread guide 32. The free thread end is held in position by the receiving funnel 35 for being felt by the guard 36, shown only diagrammatically since not forming part of the claimed apparatus, for detecting absence of the weft, and which funnel also has the task to remove occurring dust particles, so that the air in the room is maintained clean. When the reed 2 thereafter pushes the weft thread against the fell of the fabric 33, the thread at the same time, in the manner indicated above and shown in Fig. 4, is moved in between the cutting edges of the legs 21, 29 of the pair of scissors 26, whereafter the thread, after a new thread loop has been created by the catch l4 and the drum I1, is cut off by the legs of the scissors brought together. The new thread end formed in this way together with the free thread loop is blown, after a new shed has been created by means of the shafts l, 8, by the air blast through the shed 9, whereafter the process is repeated.

In Figs. 5-7 are shown another means for controlling the movements of the lever I9. 2| and an improved embodiment of the unwinding means. In this embodiment the pivot shaft 20 of the lever I9 is mounted in an arm or disc 38 extending radially from the hub 31 of the drum H, which arm is provided with a recess II for enabling the lever to swing. Both the hub 31 and the shaft 40 of the drum which shaft is mounted in ball bearings 4|, are provided with an axial passage. A displaceabie pin 42 is introduced in the part of said passage which is situated in the hub 31. One end of said pin rests against the lever 2| and its other end forms a support for one end of a. pressure spring 43, the other end of which rests against the inner end of a set screw 44 axially introduced in the passage. In the part of the passage which is situated in the shaft 44 a displaceabie bar 45 is introduced which is longer than said part of the passage. The inner end of said bar rests against the lever 2| and its outer end rests against one arm 43 of a lever 43, 41 pivoted about a shaft 43 carried by a fixed stand 49. At the other end of the lever 41 there is arranged a roller 5| rotatable about a shaft II and resting against a disc 53 driven by a shaft 52, which disc along a part of the arc-shaped path described by the roller II on said disc is provided with a slot 54 into which the roller 5| is pressed by a draw spring 55 acting upon the lever 46. When the roller engages the slot 54 the spring 43 will swing the lever |9-2| about the shaft 20 so that the pin II is moved inside the periphery of the drum I! under the action of the spring 43. The disc 53 therefore should rotate with such a velocity in relation to the drum that a suitable length of the thread I! is wound onto the drum, e. g. in one or more turns.

In the embodiment shown in Figs. 5-7 furthermore a roller 51 of rubber or any other elastic material is arranged engaging the periphery of the drum H and pivoted about a shaft 53, which roller presses the thread I0 into engagement with the drum I I before it is wound onto the latter. By using this roller of rubber the friction device |2, |3 used in the form according to Figs. 1-4 may be dispensed with. Further the advantage is obtained that a constant length of the thread I0 is always wound onto the drum ll. This causes in its turn that a constant length of thread is always fed from the nozzle 24 for which reason the thread losses at the exit end of the shed will be reduced.

Further, in the form shown in Figs. 5-7, a sleeve 58 open at both ends is arranged round the drum Said sleeve 53 which preferably should lie as close as possible to the drum I1 and should have a smooth interior surface has the task to prevent that the thread wound onto the drum at high rotation velocities of the drum is thrown outwards by the centrifugal force in the short period of time that passes between the moment when the catch it has been drawn inside the drum, and the moment when the thread is thrown out through the nozzle 24.

Finally, in the embodiment shown in Figs. 5-7, the sleeve 58 surrounding the drum H has a slot 58 through which the part of the thread l0 positioned between the roller 51 and the catch I4 is guided. Said slot 59 may preferably extend obliquely to the shaft 40 of the drum l1 substantially in the direction of winding of the thread whereby if several turns of the thread are wound onto the drum it will never lie double. The obliquely arranged slot 59 will space the thread turns from each other upon winding onto the drum as will be seen in Fig. 5.

The embodiments shown and described naturally are to be considered as an example only and the different devices of the loom may be altered constructionally in several ways within the scope of the appended claims. Thus the pair of scissors 26 may be replaced by another suitable cutting device for cutting the weft thread. The same applies to the means for creating the free loop of the weft thread. The loom may be provided in any known manner with a device for twisting the uttermost warp threads, so that the ends of the weft threads are better held in position and relatively strong selvage edges are obtained. A fine powder may be introduced in the air blast whereby the blast is better formed and effects a greater guiding force on the weft thread, when it is blown through the shed.

What I claim and desire to secure by Letters Patent is:

1. In a pneumatic loom having a substantially vertically reciprocating lay, the combination comprising a frame, means mounted on said frame for delivering a weft thread from a supply thereof, stationary jet means for blowing said weft thread through the warp shed with compressed air and means for cutting said weft thread at the entrance of said shed.

2. In a pneumatic loom having a substantially vertically reciprocating lay, the combination comprising a frame, means mounted on said frame for delivering a weftthread from a supply thereof, stationary jet means for blowing said weft thread through the warp shed with compressed air, means for cutting the weft thread at the entrance of said shed, and suction means provided at the frame and at the exit of said shed to catch the weft thread after passing through said shed.

3. In a pneumatic loom having a substantially vertically reciprocating lay, the combination comprising a frame, means mounted on said frame for delivering a weft thread from a supply thereof, comprising a rotatable drum and a catch projecting through the periphery of said drum for winding the weft thread on to said drum in one or more revolutions or part of a revolution and arranged to be retracted within the said periphery for releasing the loop of weft thread wound on said drum, stationary jet means for blowing said weft thread after being released by said catch through the warp shed by compressed air, and means for cutting the weft thread at the entrance of said shed.

4. In a pneumatic loom having a substantially vertically reciprocating lay, the combination comprising a frame, means mounted on said frame for delivering a weft thread from a supply thereof, stationary jet means for blowing said weft thread through the warp shed with compressed air, scissor means for cutting the weft thread at the entrance of said shed, guide means for said weft thread associated with the lay of the loom and provided at the entrance of said shed for moving the weft thread in between the legs of said scissor means when said thread is pushed against the already woven portion of the weaving by the lay, and cam means for closing the legs of said scissor means when the weft thread has been thus placed therebetween to out said thread.

5. In a pneumatic loom having a substantially vertically reciprocating lay, the combination comprising a frame, means mounted on said frame for delivering a weft thread from a supply thereof, comprising a rotatable drum and a catch projecting through the periphery of said drum for winding the weft thread on to said drum in one or more revolutions or part of a revolution and arranged to be retracted within the said periphery for releasing the loop of weft thread wound on said drum, and a rotatable roller of resilient material engaging said drum for pressing the part of the weft thread ahead. of said catch, as seen in the feeding direction, against said drum, stationary jet means for blowing said weft thread through the warp shed by compressed air, and means for cutting the weft thread at the entrance of the shed.

6. In a pneumatic loom having a substantially vertically reciprocating lay, the combination comprising a frame, means mounted on said frame for delivering a weft thread from a supply thereof, comprising a rotatable drum and a catch projecting through the periphery of said drum for winding the weft thread on to said drum in one or more revolutions or part of a revolution and arranged to be retracted within said periphery for releasing the loop of weft thread wound on said drum, and a stationary sleeve arranged around said drum for preventing the weft thread, after being released from said catch, from being thrown radially outwards from said drum by centrifugal force, stationary jet means for blowing said weft thread through the warp shed by compressed air, and means for cutting the weft thread at the entrance of the shed.

'7. In a pneumatic loom having a substantially vertically reciprocating lay, the combination comprising a frame, means mounted on said frame for delivering a weft thread from a supply thereof comprising a rotatable drum and a catch projecting through the periphery of said drum for winding the weft thread on to said drum in one or more revolutions or part of a revolution and arranged to be retracted within the said periphery for releasing the loop of weft thread wound on said drum, pressure means for pressing the part of the weft thread ahead of said REFERENCES CITED The following references are of record in th file of this patent:

UNITED STATES PA'I'EN'IS Number Name Date 445,395 Cranston Jan. 27, 1891 659,951 Baker Oct. 16, 1900 1,096,283 Brooks May 12, 1914 1,368,691 BIOOkS Feb. 15, 1921 1,386,550 Brooks Aug. 2, 1921 1,721,940 Ballou July 23, 1929 1,921,396 PO01 Aug. 8, 1933 

